U.S. EDGING AWAY FROM MARCOS TILT

Terry Atlas and George de Lama, Chicago TribuneCHICAGO TRIBUNE

President Reagan has authorized his special envoy to the Philippines, Philip Habib, to act as a mediator between President Ferdinand Marcos and his political challenger, Corazon Aquino, if a political compromise between them appears to be possible.

Reagan met briefly on Wednesday with Habib, his former special Middle East negotiator, amid signs that the White House is shifting away from its earlier tilt toward Marcos in the disputed vote count.

White House spokesman Larry Speakes, in a public signal to Marcos, warned him not to manipulate the election returns, which are being tallied by the Marcos-controlled National Assembly.

The credibility of the vote returns, Speakes said, will depend on ''what the Filipino people decide and what they accept,'' an allusion to the likelihood of major antigovernment demonstrations if Marcos is perceived to have stolen the election.

The apparent shift follows reports from the U.S. Embassy in the Philippines and the official U.S. election observer team, which concluded that Aquino demonstrated unexpectedly broad strength in the voting.

Senate Foreign Relations Chairman Richard Lugar (R., Ind.), who led the observer team, told Reagan on Tuesday that Aquino clearly would have won the election if not for fraud by Marcos forces.

The observer team saw indications that fraud and other abuses by the Marcos forces may have deprived Aquino of ''millions'' of votes, more than enough to have given her a clear-cut victory in a fair election, a

congressional source said. Marcos still may lose the election, he said, because ''he couldn`t steal enough votes and get away with it.''

The White House, after initially signaling that it would accept a Marcos victory despite fraud, now is beginning to focus on the need for the U.S. to help facilitate a transfer of power from Marcos to Aquino, according to administration and congressional sources.

Administration officials are discussing among themselves how a possible compromise might be structured to head off violence.

The ideas, officials said, focus on the possibility of some form of coalition government in which Marcos for the first time would cede significant power to his political opposition. But it`s not clear whether Aquino, or her vice presidential running mate Salvador Laurel, will accept such a deal if they believe they were denied a legitimate election victory.

Congressional sources predicted that Habib would press Marcos to relinquish significant power to the opposition. ''There needs to be some formula for power sharing,'' a senior State Department official said.

Lugar, who has said he was deeply disturbed by the blatant election abuses, is pressing Reagan to distance himself from Marcos.

But some sources said it`s not clear that Reagan is ready to back away from Marcos, a longtime American ally, at what is clearly a critical juncture in U.S.-Philippine relations. For instance, the President said Tuesday night that the election was marred by fraud ''on both sides,'' although the leaders of his official observer team had told him hours earlier that virtually all the cheating was on the Marcos side.

On Monday, the White House indicated that it expected Marcos to win the election and was prepared to continue to do business with him, despite election abuses. Those statements were bannered in the government-run media in the Philippines, strengthening Marcos` position and giving legitimacy to the election at the same time U.S. observers were criticizing it.

There is a growing realization in the administration that an election stolen by Marcos will disillusion Filipinos and ignite widespread unrest that would play into the hands of the already threatening communist insurgency. Aquino has said she would call for daily demonstrations against Marcos, which brought a White House rebuke Monday calling on her ''not to have demonstrations in the streets just because you didn`t like the election.''

Speakes denied that his latest remarks were intended as a green light for demonstrations by Aquino`s supporters. But, he said, ''I can`t tell the Filipino people what to do.''

In his meeting with the President Tuesday, Lugar urged Reagan not to assume a Marcos victory or to prematurely declare the election fraudulent, which could give Marcos an excuse to throw out the results and simply remain in power.

Lugar told Reagan that there has been a fundamental political transition in the Philippines and that the choice there is no longer between Marcos and Aquino, but between Aquino and the communists, a congressional source said.

Reagan met with Habib for 10 minutes Wednesday, before the President left for a speech in St. Louis followed by a brief vacation at his California ranch. Other officials at the meeting included Secretary of State George Shultz, national security adviser John Poindexter and Assistant Secretary of State Paul Wolfowitz.

Habib, a veteran Middle East negotiator, is going to Manila to assess the political situation and see whether a negotiated political compromise is possible.

''The gist of his instructions are that he will go to the Philippines and will meet with representatives of all spectrums of Philippine society--the government, the opposition, the church and others,'' Speakes said, as the President flew to St. Louis aboard Air Force One. ''It`s just an opportunity to assess the situation.''